a=input("输入竞选者一号")
b=input("输入竞选者二号")
c=input("输入竞选者三号")
d=input("输入竞选者四号")
student = {
    a :0,
    b :0,
    c :0,
    d :0,
    "无效票数" :0
}
count =0
while count <10:
    name = input("请输入你支持的候选人：")
    if name == a :
        student[a] +=1
    elif name == b :
        student[b] +=1
    elif name == c:
        student[c] +=1
    elif name == d:
        student[d] +=1
    else:
        student["无效票数"] +=1
    count +=1
print (student)
print(max(student.values()))
for key,value in student.items():
    if(value == max(student.values())):
        if ("%s"%key) == "无效票数":
            print("此次投票作废")
        else:
            print('恭喜%s成为班长'%key)
